Advanced Manufacturing Process for Production of HPT Thermal Barrier Coatings

This paper presents an economical process to make highly durable thermal barrier coatings (TBCs) for high temperature turbines. This TBCs have columnar structures with vertical cracks, similar to EB-PVD coatings.  Such structures allow the TBC to compensate for thermal expansion differences between it and the base material, resulting excellent durability. This technology combines Mettech’s axial injection plasma process and automatic slurry feed system, called Axial Suspension Plasma Spray (ASPS), which demonstrates its capability to overcome the complexities of the process. This process is proven to be reliable and durable, and is ready for industrial application. The process has significantly lower capital and operational cost compared to EB-PVD process. The ASPS process presents significant potential to replace EB-PVD for aircraft turbines, and offers an economical method to deposit thick TBCs for large land-based turbine components.